Cigarette gas lighter

ABSTRACT

Cigarette gas lighter body with a tapped well for engagement with a screw-threaded valve body. The lighter body has, above and around the tapped well, a neck formed by an outer extension with a cylindrical bore and, at the base thereof, an inner groove imparting radial elasticity to the neck.

United States Patent 1 91 Tricot 1451 May 22, 1973 [54] CIGARETTE GASLIGHTER [56] References Cited [76] Inventor: Tries, 53-, RU}: (111 ValUNITED STATES PATENTS Sm aunce rams 3,014,357 12/1961 Zellweger..222/s45 x [22] Filed: Feb. 11, 1971 3,118,295 1/1964 Van Poppel..222/3 [21] Appl' 4572 Primary Examiner-Robert B. Reeves 30 ForeignApplication priority Data Assistant Examiner-Thomas E. KocovskyAttorney-Waters, Roditi, Schwartz & Nissen Feb. 12, 1970 France..7005085 [57] ABSTRACT [52] US. Cl. ..222/3, 222/545, 431/344 Cigarettegas lighter body with a tapped well for en- [51] Int. Cl ..F23d 3/00 e swith a Screw-threaded valve y- The 58] Field of Search ..222/3, 520,545; lighter y has, above and around the pp well, a 431/344 neck formedby an outer extension with a cylindrical bore and, at the base thereof,an inner groove imparting radial elasticity to the neck. a

1 Claim, 3 Drawing Figures CIGARETTE GAS LIGHTER FIELD OF THE INVENTIONThe present invention relates to improvements in the bodies of cigarettegas lighters of the type wherein the plastic body constituting thereservoir for the liquefied gas fuel comprises a tapped well adapted toreceive a screw-threaded valve body or unit incorporating the valvemember controlling the opening and closing of the valve seat fordelivering the gaseous fuel by pressure-release action.

DESCRIPTION OF PRIOR ART In cigarette -or cigar lighters of thischaracter the gas flowing from the reservoir penetrates into the valvebody and, if the valve member is unseated, flows through this body tothe burner. Considering the necessary functional clearance to beprovided between the threaded portion of the valve body and the tappedhole of the well formed in the lighter body, adequate means must beprovided for properly sealing the joint between the wall of said welland the valve body and thus avoid any detrimental gas leakage.

As a rule, these means consist of O-rings disposed in a groove providedto this end in the valve body and registering with the upper portion ofsaid well. Although the fluid-tightness thus obtained is amplysatisfactory, the use of this conventional technique involves themachining of a groove and the fitting of the O-ring therein whichconstitutes a costly operation increasing the cost of the lighter itselfespecially in the case of cheap or lost lighter, i.e., of the typeusually thrown away when the fuel is exhausted.

To avoid this inconvenience various attemps have been made notably byproviding an injection-moulded plastic valve body formed with anintegral circular lip or flange ensuring the necessary fluid-tightnessassociated with the cylindrical inner wall of the well, the outer edgeof the lip or flange bearing resiliently thereagainst.

However, actual practice proved that this solution was not completelysatisfactory for to obtain a reliable fluid-tightness the lip, at leastin the vicinity of its free edge must have a diameter slightly greaterthan the inner diameter of said well under these conditions, it is clearthat during the assembling operation this lip undergoes a slightreduction in diameter which, due to its resiliency, cannot compress thelip material but imparts to this lip a somewhat corrugated shape which,approximately, may be compared to that of a bottle crown cap. As'aresult, the outer periphery of the lip is formed with radial splineswhich, although very small, facilitate gas leakages. Moreover, in caseof temperature increment, notably when the cigarette lighter is operatedduring relatively longtime periods, the plastic valve body expands morethan the well material so as to further increase the lip distortion andtherefore the gas leakages resulting therefrom.

SUMMARY OF THE INVENTION The improvements according to the presentinvention are intended to provide sealing means which, without undulyincrementing the cigarette-lighter assembling time, preserves itsefficiency irrespective of the temperatures likely to be encounteredunder normal or prolonged service conditions.

According to this invention, the well formed in the lighter body orreservoir for receiving the valve body comprises a neck-formingcylindrical outer extension of plastic material injection-mouldedintegrally with the lighter body or reservoir, said outer extensioncomprising at its base an inner groove imparting a certain radialelasticity thereto and, on the remaining upper portion of the neck, asmooth cylindrical bore of a diameter slightly smaller than the groovediameter and also than the outer diameter of the valve body, so thatthis inner wall resiliently engages said valve body and provides byitself the necessary gas tightness.

The importance of this cylindrical resilient neck is considerablebecause on the one hand when the valve body is introduced into the wellsaid neck is caused to expand or flare out, therefore without formingsplines or other distortions facilitating the escape of gas, and on theother hand it permits immediately, upon completion of the assemblingoperation and due to its radial resiliency, of removing the spindle orlike tool necessary for forming the inner groove recessed from the borewall.

BRIEF DESCRIPTION OF THE DRAWINGS A clearer understanding of thisinvention will be had from the following description given withreference to attached drawings illustrating diagrammatically by way ofexample two typical forms of embodiment of the invention. In thedrawings FIG. 1 is a fragmentary longitudinal section showing a firstform of embodiment of a cigarette-lighter reservoir according to thepresent invention FIG. 2 is a longitudinal detail section showing thewell of FIG. 1 before the insertion of the valve body into it, and

FIG. 3 is a view similar to FIG. 2 but showing a modified form ofembodiment.

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the drawings, the referencenumeral 2 designates a reservoir adapted to be filled with liquefied gas3 as conventional in gas lighters, the upper portion of this reservoir 2comprising a well 4 formed with a tapped portion 4a adapted to receive acorrespondingly screwthreaded valve body 5. This valve body 5 made ofsuitable metal incorporates the valve member of which the projectingupper portion constitutes the burner 6.

According to this invention, the well 4 has an outer extension in theform of a cylindrical neck or skirt 7 also formed of plastic material,notably by injectionmoulding. This neck 7 comprises an inner groove 8formed substantially at the base thereof and adapted to impart a certainresiliency to this neck. The neck 7 further comprises on its innerportion extending from this groove to its outer edge a bore 9 having abevelled upper edge 10. The diameter of bore 9 is slightly inferior tothe outer diameter of the valve body 5.

Thus, when the valve body 5 is fitted by screwing into the well 4 ittends to produce a radial expansion of the neck 7 in the direction ofthe arrows ll of FIG. 2. Thus, the neck 7 is caused to flare out inorder to facilitate the introduction of the valve body while exerting byinherent resiliency a radial clamping effort in a direction opposed tothat shown by the arrows 11.

As a result, the resiliency of neck 7 is sufficient for providing afluid-tight engagement between the wall of its bore 9 and the outer wallof valve body 5, and thus prevent any gas leakage between the valve bodyand the well.

In this specific form of embodiment, the neck 7 projects somewhat fromthe reservoir body 2, but it will readily appear to those skilled in theart that it can also be so formed that its upper face 12 besubstantially coplanar with the corresponding face 13 of said reservoir,as illustrated in FIG. 3. In this case, the neck 7 is surrounded by aconcentric groove 14 formed in the upper portion of the reservoir inorder to preserve the inherent radial resiliency of said neck 7.

It will be noted that another advantage characterizing this elasticityof neck 7 is that during the manufacturing process and after the removalof the counterpart bounding its outer contour, the spindle or like toolnecessary for machining the groove 8 can be extracted without difficultynow this step would not be possible if this resilient neck were notprovided, since said groove is recessed with respect to the bore in thewell.

Of course, this neck may also be formed integrally with the gasreservoir proper or with the cigarettelighter body in case this bodyconsisted of the reservoir itself.

It will readily appear to those conversant with the art that the presentinvention should not be construed as being strictly limited to thespecific forms of embodiment described and illustrated herein by way ofexample, since many modifications and variations may be brought theretowithout departing from the basic principle of the invention as set forthin the appended claims.

What is claimed as new is 1. In a lighter body of the type wherein aplastic container for liquefied gas has a top integrally formed with awell for receiving a valve body which has valve means therein forcontrolling release of gas from the container to provide a flame, theimprovement which comprises:

a. a tapped surface portion of the well, for engagement with ascrew-threaded lower portion of the valve body, and b. a neck, formingan integral extension of the container top, above and around said tappedsurface portion, with an inner, peripheral groove substantially at thebase of said neck, and, thereabove, an inner, cylindrical surfaceportion of said neck, for resilient inward engagement thereof, by virtueof said groove, with a slightly thicker, cylindrical, outer portion ofthe valve body, whereby said inner cylindrical surface portion bearsagainst said outer cylindrical portion and thus provides, by itself, agas-tight seal for the valve body in the neck, while permittingmovements of the screw-threaded valve body in the tapped well to adjustthe length of the flame.

1. In a lighter body of the type wherein a plastic container forliquefied gas has a top integrally formed with a well for receiving avalve body which has valve means therein for controlling release of gasfrom the container to provide a flame, the improvement which comprises:a. a tapped surface portion of the well, for engagement with ascrew-threaded lower portion of the valve body, and b. a neck, formingan integral extension of the container top, above and around said tappedsurface portion, with an inner, peripheral groove substantially at thebase of said neck, and, thereabove, an inner, cylindrical surfaceportion of said neck, for resilient inward engagement thereof, by virtueof said groove, with a slightly thicker, cylindrical, outer portion ofthe valve body, whereby said inner cylindrical surface portion bearsagainst said outer cylindrical portion and thus provides, by itself, agas-tight seal for the valve body in the neck, while permittingmovements of the screw-threaded valve body in the tapped well to adjustthe length of the flame.